HMS Challenger in St. Thomas Harbor in 1876 near the end of its
four year long expedition to explore the worlds oceans.
The Challenger was the first true oceanographic research vessel
specifically designed to investigate the biology, geology and chemistry of the oceans and seafloor.

The
Challenger ExpeditionModern oceanography began with the Challenger
Expedition between 1872 and 1876. It was the first expedition organized
specifically to gather data on a wide range of ocean features, including
ocean temperatures seawater chemistry, currents, marine life, and
the geology of the seafloor. For the expedition, HMS Challenger,
a British Navy corvette (a small warship) was converted into the
first dedicated oceanographic ship with its own laboratories, microscopes
and other scientific equipment onboard. The expedition was led by
British naturalist John Murray and Scottish naturalist Charles Wyville
Thompson. Thompson had previously dredged some curious creatures
from the ocean depths in the North Atlantic and the Mediterranean
Sea, and these discoveries persuaded the British government to launch
a worldwide expedition to explore the ocean depths. The Challenger
Expedition left Portsmouth, England, just before Christmas in 1872.
The ship had many different types of samplers to grab rocks or mud
from the ocean floor, and nets to capture animals from different
levels in the ocean. Challenger also had different winches-mechanical
engines used to lower and hoist sounding lines to measure how deep the ocean
was. At each sampling station, the crew lowered trawls, nets and other samplers
to different depths, from the surface to the seafloor, and then pulled them
back on board loaded with animals or rocks.

Challenger first traveled south from England to the South Atlantic,
and then around the Cape of Good Hope at the southern tip of Africa.
It then headed across the wide and very rough seas of the southern
Indian Ocean, crossing the Antarctic Circle, and then to Australia
and New Zealand. After that, Challenger headed north to the Hawaiian
Islands, and then south again around Cape Horn, at the southern tip
of South America where the Pacific and Atlantic Oceans meet. After
more exploration in the Atlantic, Challenger returned to England in
May of 1876.

Fun
Facts About the
HMS ChallengerExpedition Crew243
Scientists 6
Duration of Expedition 4
years
Distance
sailed 127,000
km (68,890 miles)
Number
of sampling stations362
Number
of depth soundings made 492
Number
of dredges taken 133
Number
of new species of animals and plants discovered4,700

Among the Challenger Expeditions discoveries was one of the deepest parts
of the ocean -- the Marianas Trench in the western Pacific, where the seafloor
is 26,850 feet, or more than 4 miles deep (8,200 meters). The deepest place in
all the oceans is near where the Challenger took its sounding. It is now called
the Challenger Deep and it is 37,800 feet deep (11,524 meters). The expedition
also revealed the first broad outline of the shape of the ocean basin, including
a rise in the middle of the Atlantic Ocean that we now know is the Mid-Atlantic
Ridge. Scientists compiled the first systematic plots of currents and temperatures
in the oceans. The Challenger Expeditions exciting discoveries encouraged
other countries to take interest in the oceans and to mount their own expeditions.